STELAR-S2S

2013 flood set to be one of the largest on record

The Mekong flood of 2013 is already one of the largest on record. With 63000 cumecs measured at Kratie , this year's flood sits at number four or five on the list of largest floods on record. Such a dramatic rise in the hydrograph late in the monsoon season is a result of a series of low pressure systems making landfall around the South China Sea. Of particular note was Typhoon Usagi , the most powerful typhoon of 2013, which brought high winds and rainfall of approximately 1,000 mm (39 in) to the northern part of the Mekong basin. This prompted Vietnam and Thialand to open their dams, resulting in a dramatic rise (6 m in 3 days) along the Mekong main channel. Over the past few days water levels have begun to fall, however extensive flooding has been recorded in Kratie and Phnom Penh . Despite the drop in water levels, fears remain that Typhoon Wutip will make landfall in the coming days over Vietnam, bringing further rainfall and rises in water level to a system already at capacity. This could result in the 2013 flood becoming one of the worst in recent memory.

STELAR team conduct fieldwork during monsoon

The STELAR-S2S team conducted their first monsoon field campaign in September 2013. Working their way upstream from Phnom Penh to Kratie, the team conducted high resolution bathymetric surveys of the river bed and banks using Multi-Beam Echo Sounding (MBES), as well as obtaining high-resolution flow data and suspended sediment samples at 11 high priority sites. All this work was conducted whilst on the rising limb of the monsoonal flood, as the rains from tropical storms and Typhoon Usagi forced water levels up. The timing of this trip could not have been any better, as the rising waters led to the collection of some exceptional, and exciting, data. The team plan to revisit the 11 field sites next month to capture the falling limb of the hydrograph.

STELAR team present work at Mekong Symposium

Dr Chris Hackney attended the Mekong Environmental Symposium in Ho Chi Minh City, Vietnam in early March. He presented work entitled "Decoding the hydrological drivers of river bank erosion on the Mekong River". A copy of his presentation is available here. As well as presenting research, the symposium offered a chance to interact and exchange ideas with decision makers, politicians and scientists from around the world, who have a shared interest in the future of the Mekong River system.

january field campaign

The STELAR team visitied Cambodia in January 2013 for the first field campaign of the project. The team met with members of the Mekong River Commision and the Cambodian Ministry of Water Resources and Meterology as well as undertaking reconnaissance of the 300 km study reach. A total of 188 floodplain cores, river bed- and river bank material samples were taken which will subsequently be analysed to determine rates and timing of floodplain sedimentation and grain size. Additionally the team undertook some Cohesive Strength Meter analysis of the river banks in order to determine the strength of the bank material to inform the morphodynamical modelling aspect of the project.

project meeting at AGU2012

Members of the STELAR team met with project partners Tom Drake and Charles Nittrouer during the 2012 AGU Fall Meeting in San Francisco, USA. Possible synergies between the STELAR project and the Office of Naval Research (ONR) project were discussed. Both strive to understand the sediment transfer dynamics within the Mekong River system. Where the STELAR field area ends the ONR begins providing an exciting opportunity to understand sediment transfer within the Mekong system from source to sink.

inaugural fieldwork campaign

The STELAR team will visit Cambodia in January 2013 for our first fieldwork campaign. The team will hold meetings with key partners in Phnom Penh, and undertake a reconnaissance of the study reach to help finalise study site selections and plans for the next phase of work during the summer 2013 monsoon flood. While they are in Cambodia the team will also collect bed and bank material samples to aid in the physical characterisation of the river, and extract sediment cores that will later be analysed using Pb-210 and Cs-137 geochronology at Exeter to help determine the rates and timing of floodplain sedimentation.

STELAR team to present at Mekong Symposium

Dr Chris Hackney will be attending the Mekong Environmental Symposium in Ho Chi Minh City (5th-7th March 2013). Look out for Chris’ presentation on the influence of climate variability on Mekong River bank erosion and do talk to him if you’d like to learn more about our work.